Process for producing alcohols from hydroxy carboxylic compounds



Patented Oct. 5, 1937 UNITED STATES 2,094,611 rnoccss FOR PRODUCINGALCOHOLS FROM POUNDS HYDROXY CARBOXYLIC COM- Wilbur .A. Lazier,'Marshallton, DeL, assignor to E. I. du Pont de Nemours & Company,Wilmington, Del., a corporation of Delaware No Drawing.

Application December Serial No. 757,071

64 Claims. (Cl. 260-4565) This invention relates to catalytic processesfor the production of organic compounds of an alcoho1iccharacter. Moreparticularly it relates to a process for the catalytic reduction bymeans of elementary hydrogen of hydroxy-carboxylic acids, their esters,and their anhydrides to the corresponding glycols. Specifically, theinvention relates to the use of certain catalysts especially well suitedto the hydrogenation of hydroxy acids and their .derivatives to thecorre- ,sponding glycols, and to processes for the production ofoctadecanediol from castor oil and its derivatives.

This application is a continuation-in-part of my co-pending applicationSerial No. 584,576, which was filed January 2, 1932, as acontinuation-in-part of applications Serial Nos. 520,473 and 520,474,both filed March 5, 1931. Application Serial No. 520,474 has sincematured into U. S. Patent 1,839,974. The present application is also acontinuation-in-part, of the following co-pending applications: SerialNo. 629,754 filed August 20, 1932, which in turn was acontinuation-in-part of Serial No. 445,224 filed April 17, 1930; SerialNo. 584,574 filed January 2, 1932; and Serial No. 715,509 filed March14, 1934.

For many years the only known methods for the reduction ofhydroxy-carboxylic acids, esters, and their anhydrides to. thecorresponding glycols were purely chemical reactions involving theconsumption of expensive reducing agents. The most successful procedurewas that outlined by Bouveault and Blane (Chem. Zentr. 1904, II, 184;1905, II, 1700). This process involves preparing an ester of the acid tobe reduced and the use of metallic sodium and absolute alcohol as thereducing agent. Thus it has been possible to prepare alcoholicderivatives ofthe simple aliphatic carboxylic acids. This method,however, is so costly as to render its use prohibitive for themanufacture of various glycols which might otherwise be very useful inthe arts.

By suitable modifications, of processes fully described in theco-pending specifications to which reference has already been made, ithas now become possible to realize on a commerfial scale a technicallyand economically successful catalytic hydrogenation of hydroxy acids,their esters, and their anhydrides, whereby glycols are formed whichcorrespond in the number of carbon atoms to the acids or acidderivatives subjected to the hydrogenation treatment. Other productssuch as the corresponding saturated hydrocarbons and esters of the newlyformed glycols may also be prepared in this way by'minor I variations inthe procedure, but the invention is primarily concerned with theproduction of glycols which are the intermediate products between theesters of the glycols and the corresponding hydrocarbons resulting fromexhaustive hydrogenation.

In my co-pending application Serial No. 520,473, filed March 5, 1931,there is contained a description of the successful hydrogenation ofnatural glyceryl esters known as fats and fatty oils, and there isspecifically described in Example 4 the hydrogenation of castor oil. Thehydrogenation process therein described effects the hydrogenation of theester group of the glyceride, thereby yielding alcohols. This type ofhydrogenation is to be distinguished sharply from the process ofhardening fats by hydrogenation as practiced at a much earlier date, andwhich consists in agitating a glyceride of an unsaturated fatty acidwith a suspended nickel catalyst in the presence of gaseous hydrogenunder a pressure slightly in excess of atmospheric pressure. In theprocess of hydrogenating fats and fatty oils as practiced in the priorart, the temperatures employed are usually 50 to C; and are nevergreater than 200 C., while the pressures customarily used aresubstantially atmospheric.

This invention has as an object to provide a process for the conversionof hydroxy-carboxylic acids, their esters, and their anhydrides to thecorresponding glycols. It is a further object of the invention todisclose processes for the hydrogenation of castor oil, ricinoleic acid,hydroxystearic acid, and derivatives of the same, and the productsproduced by such hydrogenation. A more specific object is thepreparation of octadecanediol which is a new compound.

The processes of my inventionare characterized by the use of an excessof hydrogen and temperatures and pressures much inexcess of thoseordinarily employed. In general, the invention is carried out bybringing the hydroxyrcarboxylic compound and hydrogen into intimatecontact with a suitable alcohol-forming catalyst at relatively hightemperatures and pressures. There are, however, several modifications ofthe general process. For example, a mixture of the compound to behydrogenated, solid catalyst, and

gaseous hydrogen maybe brought together at high temperatures andpressures with suitable agitation in a closed autoclave capable ofWithstanding the necessary pressure. -In this case the catalyst ispreferably a composition containing copper, either in the elementaryform or combined with oxygen as a lower oxide. Other hydrogenating metaloxides may be employed in conjunction with copper, or suitable catalystsupports such as kieselguhr. silica gel, and activated carbon may beused. In another modification, of the process the hydroxy-carboxyliccompounds and hydrogen are passed under high pressures and elevatedtemperatures over mixed hydrogenation catalysts containing substantialquantities of diflicultly reducible oxides of hydrogenating metalsprepared in a suitable granular form and held in place in apressure-resisting tube. Contrary to expectation, it has been found thatunder high hydrogen pressures, hydroxy acids and their derivatives are,much less susceptible to decomposition by heat than would be supposedfrom their behavior when heated in air. Under reducing. conditions andin the presence of a suitable catalyst the decomposition, if such it maybe termed, takes place in a controlled manner and with the absorption ofhydrogen and the production of the corresponding dihydric alcohols.

The following examples are illustrative of some of the methods that maybe employed in the practice of my invention:

Example I A hydrogenation catalyst is prepared as follows: 23 g. ofcadmium nitrate, 24g. of copper nitrate and 245 g. of zinc nitrate aredissolved in 500 cc. of water and mixed at ordinary temperature with anequal volume of water containing 126 g. of ammonium bichromate and cc.of 28% ammonium hydroxide. After stirring, the mixture is exactlyneutralized with additional ammonium hydroxide and allowed to settle.After several washes by decantation, the precipitate is dried, ignitedat 400 C. and compressed into tablets or grains suitable for use incatalytic gas apparatus.

Twenty-five cc. of the mixed chromite catalyst prepared as describedabove was loaded into an alloy steel reaction vesselcapable of beingheated and withstanding high pressures. The tube was fitted with apreheater, a pump for injecting liquid ester at a constant rate, a T-connection for introducing hydrogen under pressure, a suitable condenserand trap for separating liquid products, and exit control valve. Ethylricinoleate was passed with hydrogen over the catalyst at a rate ofabout 200 cc. per hour. The average pressure was 2570 pounds per squareinch, the average temperature 370 C., and the rate of hydrogen flow 7.7cubic feet per hour. The saponification value of the condensed productindicated a conversion to alcohols amounting to about 65%. In order toremove the remaining oleflnic unsaturation, the products were subjectedto a further -hydrogenation with a nickel catalyst in the liquid phaseat C. After distilling off the ethyl alcohol there remained a whitesolid material consisting of about equal parts of octadecanediol andstearyl alcohol, together with a lesser amount of the esters of thesealcohols. v

Example II Castor oil maintained under 2700 pounds per square inchhydrogen pressure was passed at a temperature of 400 C., together withhydrogen, at a space velocity of 4 volumes of oil per volume of catalystper hour and at a molecular ratio of 12 moles of hydrogen per mole ofcombined ricinoleic acid over-25 cc. of the zinc-copper-cadmium chromitecatalyst describe: in Example I. The

decrease in saponiflcation value was about 60%. while the iodine numberwas lowered from 65 to 55. The product was quite fluid and possessed apleasant alcoholic odor. By further hydrogenation with nickel in theliquid phase by the prior art method, namely, at a temperature of 50 toC., and at a pressure slightly in. excess of atmospheric pressure, theproduct was readily converted to a white solid material, containing alarge proportion of a dihydric alcohol. The crude product had an acidnumber of: 3. a saponiflcation number of 80, an iodine number of 4, andan acetyl number of 171.

The following procedure was used to separate out the octadecanediol fromthe crude mixture; One thousand grams of the white solid material wassaponified by refluxing for 8 hours with a solution of 70 g. of sodiumhydroxide dissolved in 2.5 liters of water. The soapy mass wasevaporated and dried. The residue was broken up and continuouslyextracted with ether in small batches. The various portions of etherextract were combined, and the ether distilled 01f.v The residue waswashed with hot water and dried. Four hundred thirty-one grams ofproduct was obtained, of which 376 g. was fractionated through a 15 inchlagged Vigreux column at 0.1 mm. pressure, (gauge reading) with thefollowing results:

Fraction 5 was refractionated at 0.5 mm., the first 10 g. of distillatebeing discarded. The remainder distilled at to 182 C., with the bathtemperature at 225 to 235 C. The latter part of the distillate melted at66 to 67 C., and was quite pure octadecanediol-1,12.

Analysis: Calculated for C18H38o2: C, 75.52; H, 13.29.

Found: C, 75.66, 75.65; H, 12,96, 13.26.

octadecanediol is a white solid melting at 66 to 67 C., and boiling at180 to 182 C. at a pressure of 0.5 mm. The glycol has an acetyl numbercorresponding to a dihydric alcohol. It contains one primary and onesecondary alcohol group. The compound appears to be crystalline but isvery waxy in character. It dissolves in alcohol or ether. It is notreadily soluble in water but may be emulsified at temperatures above themelting point.

Example III A good commercial grade of ricinoleic acid produced bysaponiflcation of castor oil was hydrogenated continuously to producehigh yields of glycol. The zinc-copper-cadmium chromite catalystdescribed in Example I was heated to a temperature of about 380 C. Theacid was pumped over 100 cc. of the catalyst at the rate of about 200cc. per hour. The hydrogen pressure was 2500 to 3000 pounds per squareinch, and the rate of flow of the hydrogen about 15 cubic feet per hour.Under these conditions the ricinoleic acid is hydrogenated in the vaporphase. There was produced a viscous product containing about 40% ofesters and practically no free acid, the remainder being, with theexception of a small amount of glycerol, practically all long-chainhigher alcohols. t The reaction products were susceptible of furtherhydrogenation and purification in the same manner as described inExample II to produceloctariecanediol.

nitrate and-176 grams of chromic acid were dissolved in 2760 cc. ofwater and 88 g. of anhydrous .ainmonia was added to the solution withagitation during a period of to minutes. The precipitate was filtered,washed once on the filter and dried, after which it was ignited at 500C.

. pressure of 600 atmospheres.

The resulting copper chromite powder was extracted twice by stirring itfor 15 minutes each time with a solution of 200 g. of glacial aceticacid in 1800 cc. of water. After extraction, it was washed free fromacid, filtered, dried and screened through a 20 mesh screen. Two hundredseventy-five grams of this catalyst and 4330 -g. of ethylhydroxystearate were placed in an autoclave and hydrogen was introducedto a pressure of 3000 pounds per square inch. The mixture was thenheated to 350 C. and agitated for 9 hours, after which hydrogenabsorption had ceased. The decrease in saponification number of theester during this treatment corresponded to hydrogenation of thecarboxyl groups while recovery and separation of the product yielded 12%stearyl alcohol and- 80% octadecanediol.

Example V Twenty-six grams of barium nitrate and 218 g. of cupricnitrate were dissolved in 0.8 liter of water by heating to 70 C. Asolution of 128 g. of ammonium bichromate and 0.15 liter of 28% ammoniumhydroxide in 600 cc. of water was added with stirring. The precipitatewas filtered; dried and ignited at 400 C. The ignition residue was thenextracted twice with 10% acetic acid, washed and dried. Twenty grams ofthis copper barium chromite was agitated with 340 g. of ethylalpha-hydroxy isobutyrate under a hydrogen pressure of 2500 pounds persquare inch. Hydrogen absorption was rapid at about 200 C. and thereaction was complete in about one hour. On distillation of the product,there was obtained a 91% yield of 2-methyl propane diol-1,2.

Example VI One hundred fifty grams of ethyl citrate'and 12 g. of thecopper barium chromite catalyst prepared as described in Example V werecharged into a steel reaction tube built to withstand high pressure. Thetube was agitated for 4.5 hours at a temperature of 240 C. and ahydrogenation From the reaction product there was isolated 25 g. of atrihydric alcohol (trimethyiol propane) and an oily residue containing asubstantial quantity of a cyclic ether alcohol, the constitution ofwhich was not fully determined.

Example VII Fifteen hundred grams of copper nitrate dissolved in 4liters of water was mixed with a solution containing 1000 g. of ammoniumchromate in an equal volume of water. Ammonium hy-, droxide was added toneutralize the acidity developed during precipitation of the copperammonium chromate. The precipitate was washed by decantation, filtered,and dried, after which it was ignited at a temperature of 400 .C. Theignition residue was then extracted twice with 10% acetic acid, washedand dried.

Two hundred grams of gamma hydroxy valeric ester was subjected tohydrogenation in the pres- Example VIII Three hundred and twenty gramsof a copperbarium-chromite catalyst prepared as described in Example Vand 4000 grams of 12-hydroxy stearin (hardened castor oil) were placedin a stirring autoclave and hydrogen was introduced to a pressure of3000 pounds per square inch which was maintained throughout the run. The

;mixture was then heated to 260 C. and agitated for seven hours, afterwhich hydrogen absorption had ceased. After removal of the products fromthe autoclave and filtering, the alcohols thus obtained solidified to ahard solid having a melting point of about. 65 C. The decrease insaponification number of the oil during hydrogenation corresponded to a92% conversion of the carboxyl groups, while the hydroxyl value of 347obtained by analysis of the product indicated a substantially completeconversion of the hydroxy stearin to the correspondingoctadecanediol-1,12.

' Example IX Sixteen grams of a copper chromite catalyst prepared asdescribed in Example IV, 0.4 g. of magnesium oxide, and 200 g. of ethylhydroxystearate were charged into a steel reaction tube Example X Coppercarbonate was prepared by dissolving 720 g. of copper nitrate trihydratein 1 liter of water and heating the solution to 40 C. and slowly addingwith agitation during a period of one hour a solution consisting of 300g. of sodium carbonate dissolved in 3 liters of water. The precipitatethus formed was washed four times by decantation using 5liters ofdistilled water for each wash, after which it was filtered, dried at C.,and ground to a fine powder. An intimate mixture consisting of 25% ofcopper carbonate prepared as described and 75% of copper barium chromiteprepared as described in Example V was made by grinding the twocomponents in a mortar. Sixteen grams of the above catalyst mixture and200 g. of castor oil were heated in a steel reaction tube to atemperature of 260 C. under a'hydrogen pressure of 3000 pounds persquare inch with continuous agitation for a period of 12 hours, duringwhich time a reduction in saponification value of the oil occurredequivalent to 99% conversion of the carboxyl group while the iodinenumber was reduced to less than 1.0. The hydroxyl value of theprodcontact of the material treated with the catalyst have beenindicated in the above examples, it will be apparent that these factorsmay be varied within wide limits within the scope of my invention. Thecatalytic reduction of hydroxy acids, their esters, and their anhydridesto alcohols or glycols requires the use of temperatures and pressuresappreciably higher than customarily employed for other hydrogenationreactions. The temperature may range from above 200 C. up to 500 C. Thepreferred temperature range is 240 to 400 C., depending somewhat on thecatalyst-- pressures in excess of atmospheres, while the preferredpressure is 50 to 400 atmospheres. The maximum pressure which can beused is limited only by the strength ,of the reaction apparatus.

I and hydrogen.

Whereas the critical factors and inventive steps in the hydrogenation ofhydroxy-carboxylic compounds to glycols are the use of high temperaturesand pressures, it necessarily follows that suitable catalysts -may beselected from among a number of different hydrogenating metals andoxides.

Mild-acting hydrogenating catalysts such as metallic copper and zincoxide which are well known to be suitable for the synthesisof methanolfrom carbon monoxide and hydrogen are in general also suitable catalystsfor the production of glycols. On the other hand; there are certain veryenergetic catalysts such as metallic nickel and iron which are known tocatalyze the formation of hydrocarbons from oxides of carbon Theseferrous metal catalysts, when employed in the hydrogenation of hydroxyacids and their esters, tendto carry the reaction too far with theformation of hydrocarbons. Therefore, if the hydrogenation is to beoperated for the production of alcohols and glycols to the substantialexclusion of hydrocarbons, it is preferable to select as the catalyst acomposition comprising a member of the group of non-ferroushydrogenating metals such as copper, tin, silver, cadmium, zinc, lead,their oxides and chromites, and oxides and chromites of manganese, andmagnesium. Especially good results are obtained with finely dividedcopper oxide, either wholly or partially reduced and preferablysupported upon an inert surface-extending material such as kieselguhr,or promoted by such oxide promoters as manganese oxide, zinc oxide,magnesium oxide, or chromium oxide. The above mentioned mild-actingcatalysts may be termed the alcohol-forming catalysts to distinguishthem from the more energetic hydrocarbon-forming elements of theplatinum and ferrous metal'groups. Elementary nickel, cobalt, and iron,when suitably supported on kieselguhr, may be used to effect thereduction of carboxylic compounds with hydrogen, but in these cases theproduct contains besides alcoholic bodies a preponderance ofhydrocarbons, and this disadvantage in most cases will prove so seriousas to preclude the use of these catalysts unless the hydrocarbonsthemselves are the desired end products.

Catalysts suitable for use in the liquid phase batch method ofhydrogenation are preferably prepared in a powder form. The preferredcatalyst for this purpose is usually a copper chromite prepared byigniting a double copper amaooaeu monium chromate to its spontaneousdecomposition temperature as described in U. 8. Patent 1,746,783. Manymodifications of this procedure have been practiced involving the use ofacid. extraction, hydrogen reduction, and the use of a supplementarysupport such as kieselguhr, but these are modifications in degree only.The es- :sential feature is the use oi copper oxide intimatelyassociated or combined with chromium sesquioxide and the chromite methodof preparation is a convenient method for effecting the desiredassociation. The method, however, is not limited to copper but may bepracticed in the preparation also of zinc chromite, silver chromite,manganese chromite, etc.-

For use in the continuous flow method of hydrogenation certain metaloxides belonging to the class of difllcultly reducible hydrogenatingoxides may be conveniently employed on account of their rugged characterand the ease with which they may be-shaped into hard granules forloading into stationary apparatus. By the term diflicultly reducible" ismeant that the oxides are not substantially reduced to metal byprolonged exposure in a state of purity to the action of hydrogen atatmospheric pressure and at a temperature of 400 to 450 C. Such oxidessuitable for use as catalysts in the hydrogenation of hydroxy-carboxyliccompounds are zinc oxide, manganese oxide, and magnesium oxide. Theseoxides may be employed either alone or in combination with each other orwith other metals or oxides which have a promoting action. Preferablythe dimcultly reducible hydrogenating oxides also are prepared in theform of chromites as already indicated in the examples.

Hydroxy acids and their derivatives are particularly susceptible topartial dehydration, and it has been found that this undesirable sidereaction may be largely prevented by employing a mild inorganic baseadded to the hydrogenation catalyst. For example, products having muchhigher hydroxyl values are obtained if a little magnesia, zinc oxide,lime, or barium hydrate is added to the catalyst or to the reactionsystem. Preferably the alkali earth buffer is incorporated into thecatalyst at the time of its precipitation.

In carrying out the hydrogenation of hydroxycarboxylic compounds in acontinuous reaction system, the rate at which the ester may be pumpedover the catalyst with satisfactory results is a function of thecatalytic activity and also of the molecular weight of the ester. Anactive hydrogenating catalyst will ordinarily convert eight times itsvolume of ester per hour. Higher rates of flow of the ester may beemployed at the expense of slightly lower conversion.

The processes of the present invention are applicable to a large numberof hydroxy-carboxylic acids, their esters and anhydrides, for example,lactic, ricinoleic, hydroxy-butyric and -isobutyric, hydroxy-valeric,hydrcxy-stearic acids, etc.- As indicated, these acids may be employedfor hydrogenation in the form of the free acid or as their esters oranhydrides. The same glycols are obtained on hydrogenation irrespectiveof the form in which the hydroxy-carboxylic compound is treated. Theester may be a mono-alkyl ester or an ester of a polyhydric alcohol suchas glycerol. The hydroxy acid may be unsaturated as in the case ofricinoleic acid or fully saturated as in the case of hydroxy-stearicacid. The hydrogenation of these acids and their derivatives lead to avery interesting new glycol, i. e., octadecanediol-LIZ.

Castor oil is a glyceride of ricinoleic acid, and complete or partialreduction of the carboncarbon unsaturation may occur as in the usualhydrogenation process of the prior art, but in the present process thisis only incidental to the more-important reaction of hydrogenation ofthe ester groupwhich results in the formation of alcohols. As an addedstep in my invention, I

- sometimes prefer after conducting the reaction as indicated above tofavor alcohol formation, to hydrogenate the reaction products at lowpres sure and temperature with a nickelcatalyst in the usual mannerknown to the art. This brings all the reaction products up to the samelevel of hydrogen saturation, yielding new compositions, the mostimportant of which is octadecanediol. Alternatively, the hydrogenationwith nickel may precede the carboxylic hydrogenation carried out for thepurposes of converting the carboxyl groups to' carbinol groups, as, forexample, in the conversion of ethyl. ricinoleate to the hydroxy stearatefollowed by conversion to octadecanediol.

The hydrogenation products obtained by the hydrogenation of castor oilunder the conditions of the present invention consist of a mixture ofhigher alcohols and other products and this mixture in itselfconstitutes a new composition of matter, which in some instances findsuse in the arts without any separation of the product into itscomponents. In such cases, as well as when it is not feasible toseparate the alcohols from the other hydrogenation products, thepresence of the alcohols and the amount thereof formed may bedemonstrated conclusively by determination of the acetyl or hydroxylvalues.

Depending on the conditions of hydrogenation, a part of the secondaryhydroxyl group of octadecanediol may be split off, giving a monohydricalcohol as one of the products. The method for isolating the glycoldisclosed in Example I involves saponification and extraction. A moresimple procedure for commercial operation consists in hydrogenatingricinoleic acid or its esters rather completely and separating theglycol produced by direct vacuum fractional distillation of the crudehydrogenated product. The wax residue may then be put through thehydrogenation step again, together with fresh raw material.

From the foregoing it will be apparent that I have developed an economicmethod for obtaining octadecanediol- 1,12 from castor oil, ricinoleicacid, ethyl ricinoleate, ethyl hydroxy stearate, hydroxystearin, etc.,without the use of expensive chemical reagents and at a'small. cost perunit of product. In addition, I have made possible the preparation ofnovel alcohols and other derivatives from castor oil. Octadecanediol,the new saturated alcohol described above, has many unique propertieswhich make it of value for many industrial applications, whether it bein pure or in crude form. It is suitable for use as a cosmetic base whencombined with face creams, especially those of the vanishing type. Itswaxy properties may be utilized in paper or other finishes or infurniture, floor or automobile polishes. It is suitable for use incompounding rubber or in synthetic resins and as a softener for coatingcompositions. As a component of soap, octadecanediol contributes todetergent power in the presence of hard water and tends to counteractthe harshness of soaps. The derivatives of octadecanediol such as estersthereof find use as softeners, for example, in nitrocellulosecompositions, and the sulfonated octadecanediol is a. valuablewetting-out agent and detergent.

The above examples and descriptions are intended to be illustrative onlyand not as limiting the scope of the invention. Any modifications orvariations thereof wh ch conform to the spirit of the invention areintended to be included within the scope of the claims.

I claim:

1. A process for producing alcohols from hydroxy carboxylic compounds,which comprises bringing hydrogen and amember of the class consisting ofthe hydroxy carboxylic acids, and their esters into contact with amild-acting hydrogenation catalyst at a temperature in excess of 200 C.and at a pressure in excess of 10 atmospheres.

2. Process according to claim 1 characterized in that the temperature ismaintained between 200 and 500", C.

3. Process according to claim 1 characterized in that the temperature ismaintained between 240 and 400 C.

4.'Process according to claim .1 characterized in that thepressure ismaintained between and 400 atmospheres.

5. Process according to claim 1 characterized in that the catalyst is ahydrogenation catalyst of the class consisting of mild actinghydrogenating metals, their oxides and chromites, the oxides andchromites of manganese and magnesium, and mixtures of such metals,oxides and chromites.

6. Process according to claim 1 characterized in that the catalyst is amild-acting alcohol forming hydrogenation catalyst.

'7. Process according to claim 1 characterized in that the catalyst is acatalyst containing copper as an essential ingredient.

8. Process according to claim 1 characterized in that the catalystcomprises essentially a mixed chromite of cadmium, copper and zinc.

9. Process according to claim 1 characterized in that the catalystcomprises essentially a (hillcultly reducible hydrogenating metal oxide.

10. Process according to claim 1 characterized in that the catalystcomprises essentially a mixture of difficultly reducible hydrogenatingmetal oxides.

11. Process according to claim 1 characterized in that the catalystcomprises essentially a chrosure slightly in excessof atmospheric and ata v temperature between 50 and 200 C. in the presence of a nickelcatalyst in order to saturate the carbon-carbon bond, then subjectingthe products produced by the second hydrogenation step to separation andpurification.

16. A' process for producing a glycol, which comprises bringing hydrogenand a hydroxy carboxylic acid into contact with a mild-actinghydrogena'tion catalyst at a temperature in excesspheres. Y 17. Processaccording to claim 16 characterized that the' catalyst is ahydrogenation catalyst .01 the class consisting of mild actinghydrogenatin that the catalyst contains as essential ingredientschromites of copper and barium.

20. .4 process for producing a glycol, which comprises bringing hydrogenand an ester of hydroxy carboxylic acid into contact with a mildactinghydrogenation catalyst. at a temperature in excess of 200 C. and at apressure in excess 01' atmospheres.

21. Process according to claim 20 characterized in that the catalyst isa hydrogenation catalyst of the class consisting of mild actinghydrogenating metals, their oxides and chromites, the oxides andchromites of manganese and magnesium, and mixtures of such-metals,oxides and chromites.

22. Process according to claim 20 characterized in that the catalystcontains a small amount of an alkali earth buffer.

23. Process according to claim 20 characterize in thatthe catalystcontains as essential ingredients chromites of copper and barium.

24. A process for producing a glycol, which comprises bringing hydrogenand ricinoleic acid into contact with a mild-acting hydrogenationcatalyst at a temperature in-excess of 200 C.

and at a pressure in excess of 10 atmospheres.

25. The process according to claim 24 characterized in that the catalystis a difllcultly reducibleoxide of a hydrogenating metal.

26. The process according to claim 24 characterized in that the catalystis a mixture of difllcultly reducible oxides by hydrogenating metals.

27. The process according to claim 24 characterized in that the catalystcomprises essentially a chromite of a hydrogenating metal.

28. The process according to claim 24 characterized in that the catalystcomprises essentially a mixture of chromites of hydrogenating metals.

29. The process according to claim 24 characterized in that the reactionis carried out in the vapor phase and hydrogen is present in excess.

30. The process according to claim 24 characterized in that the reactionis carried out at a temperature between 300 and 400 C.

31. The process according to claim 24 characterized in that the reactionis carried out at a pressure between 100 and 250 atmospheres.

32. The process according to claim 24 characterized in that the reactionis carried out at a temperature between 300 and 400 C. and at a pressurebetween 100 and 250 atmospheres.

33. A process for producing alcohols from castor oil, which comprisessaponifying castor oil to form an acid, passing said acid and hy--drogen over a hydrogenation catalyst of the class consisting of mildacting hydrogenating metals, their oxides and chromites, the oxides andchromites of manganese and magnesium, and mixtures of such metals,oxides, and chro- 2,094,041 of 200 C. and at a pressure in excess of -10atmosmites at a temperature in excess oi! 200 C. and at a pressure inexcess or 10 atmospheres.

34. The process according to claim 33 characterized in that thehydrogenated reaction products are subjected to further hydrogenation toremove the carbon-carbon unsaturation. 35. A process for producingalcohols from castor oil, which comprises saponifyin'g castor oil toform an acid, then passing said acid and hydrogen over a mixture 01' thechromites of zinc, copper, and cadmium at a temperature of about 380 C.and at a pressure of about 2500 to 3000 pounds per square inch.

36. A process for producing alcohols 'from ricinoleyl derivatives whichcomprises passing ricinoleic acid .and hydrogen over a hydrogenationcatalyst of the class consistingo! mild acting hydrogenating metals,their oxides and chromites, theoxides and chromites of manganese andmagnesium, and mixtures of such metals, oxides and chromites at atemperature in excess of 200 ,C. and at a pressure in excess oi! 10atmospheres, separating the glycol produced by direct vacuumdistillation of the crude hydrogenated product.

37. Process according to claim 24 character- 40. Process according toclaim 24 characterized in that the hydrogenated reaction products aresubjected to further hydrogenation to remove the carbon-carbonunsaturation and then recovering the octadecanediol formed.

41. Process according to claim 24 characterized in that the hydrogenatedreaction products are subjected to further hydrogenation under apressure slightly in .excess of atmospheric and 'at a temperaturebetween 50 and 250 C.- in the presence of a nickel catalyst to saturatethe carbon-carbon bond; then separating and purifying the octadecanediolformed.

42. A composition containing essentially an alcohol which is obtainableby the hydrogenation of ricinoleic acid, at a temperature in excess of.

200 C. and at a pressure in excess of 10 atmospheres, in the presence ofa mild-acting hydrogenation catalyst.

43. A process of producing a glycol which comprises bringing hydrogenand an ester of ricinoleic acid into contact with a mild-actinghydrogena tion catalyst at a temperature in excess of 200 C. and at apressure in excess 01' 10 atmospheres.

44. The process according to claim 43 characterized in that the catalystis a difflcultly reducible oxide of a hydrogenating metal.

45. The process according to claim 43 characterized in that the catalystis a mixture of difllcultly reducible oxides of hydrogenating metals.

46. The process according to claim 43 characterized in that the catalystcomprises essentially a chromite of a hydrogenating metal.

47. The process according to claim 43 characterized in that the catalystcomprises essentially a mixture of chromites of hydrogenating metals.

48. The process according to claim 43 characterized in that the reactionis carried out in the vapor phase and hydrogen is present in excess.

49. The process according to claim 43 characterized in that the reactionis carried out at a temperature between 300 and 400 C.

50. The process according to claim 43 characterized in that the reactionis carried out at a pressure between 100 and 250 atmospheres.

51. The process according to claim 43 characterized in that the reactionis carried out at a temperature between 300 and 400 C. and at a pressurebetween 100 and 250 atmospheres.

52. A process for producing alcohols from castor oil, which comprisespassing castor oil and hydrogen over a mixture of the chromites or zinc;copper, and cadmium at a temperature 01 about 300-400 C. and at apressure of about 2700 pounds per square inch.

53. A composition containing essentially octadecanedio1-1,12. I

54. Octadecanediol-1,12.

55. A process for producing a glycol whichv comprises bringing hydrogenand castor oil into contact with a mild-acting hydrogenation catalyst ata temperature in excess of 200 C. and'at a pressure in excess of 10atmospheres.

56. The process according to claim 55 characterired in that the catalyst.is a hydrogenation catalyst of the class consisting of mild actinghydrogenatlng metals, their oxides and chromites, the oxides andchromites of manganese and magnesium, and mixtures of such metals,oxides and chromites.

57. The process according to claim 55 characterized in that the catalystcontains a small amount of an alkaline earth bufler.

, 58. The process according to claim 55 characterized in that thecatalyst contains as essential ingredients chromites of copper andbarium.

59. The process according to claim 55 characterized in that thehydrogenated reaction products are subjected to further hydrogenation toremove the carbon-carbon unsaturation and then recovering theoctadecanediol formed.

60. The process according to claim 55 characterized' in that thehydrogenated reaction. products are subjected to further hydrogenationunder a pressure slightly inexcess of atmospheric and at a temperaturebetween and 250 C.;in the presence of a nickel catalyst to saturate thecarbon-carbon bond, then separating and purifying the octadecanediolformed.

61. A mixture of alcohols obtainable by the carboxyl hydrogenation ofcastor oil.

62. A mixture of alcohols obtainable by the carboxyl hydrogenation ofcastor oil followed by the hydrogenation of the resulting product with anickel catalyst in order to remove the carbon-carbon unsaturation.

63. A mixture of alcohols obtainable by the carboxyl hydrogenation ofthe mixture of acids obtained by the hydrolysis of castor oil. v

64. A mixture of alcohols obtainable by the carboxyl hydrogenation ofthe mixture of acids obtained by the hydrolysis of castor oil followedby the hydrogenation of the resulting product with a nickel catalyst inorder to remove the WILBUR A. LAZIERn

